BoilerFaultCodesWhat the manual says
Manufacturer manualFan frost protection function active: Air pressure switch fault - Pressure monitor has not switched or has switched at a fan speed value that is too high (insufficient air supply), Pressure monitor plug not correctly plugged in, pressure monitor defective, hose removed from between the pressure monitor and silencer, air/flue pipe blocked
From this model's manual
Verified against the Vaillant/Vaillant Home Regular Installation And Maintenance installation & service manual.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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All 33 fault codes on the Home Regular 12
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